<?php
defined('BASE') or exit('Access Denied!');

/**
 * Obullo Framework (c) 2009.
 *
 * PHP5 MVC Based Minimalist Software.
 * 
 * @package         obullo       
 * @author          obullo.com
 * @copyright       Ersin Güvenç (c) 2009.
 * @filesource
 * @license
 */

Class PagerException extends CommonException {}
 
// ------------------------------------------------------------------------

/**
 * Obullo Pagination Class
 *
 *
 * @package       Obullo
 * @subpackage    Libraries
 * @category      Libraries
 * @author        Ersin Güvenç
 * @link          
 */
class OB_Pager {

    public $base_url            = ''; // The page we are linking to
    public $total_rows          = ''; // Total number of items (database results)
    public $per_page            = 10; // Max number of items you want shown per page
    public $num_links           =  2; // Number of "digit" links to show before/after the currently viewed page
    public $cur_page            =  0; // The current page being viewed
    public $first_link          = '&lsaquo; First';
    public $next_link           = '&gt;';
    public $prev_link           = '&lt;';
    public $last_link           = 'Last &rsaquo;';
    public $uri_segment         = 3;
    public $full_tag_open       = '';
    public $full_tag_close      = '';
    public $first_tag_open      = '';
    public $first_tag_close     = '&nbsp;';
    public $last_tag_open       = '&nbsp;';
    public $last_tag_close      = '';
    public $cur_tag_open        = '&nbsp;<strong>';
    public $cur_tag_close       = '</strong>';
    public $next_tag_open       = '&nbsp;';
    public $next_tag_close      = '&nbsp;';
    public $prev_tag_open       = '&nbsp;';
    public $prev_tag_close      = '';
    public $num_tag_open        = '&nbsp;';
    public $num_tag_close       = '';
    public $page_query_string   = FALSE;
    public $query_string_segment = 'per_page';

    /**
     * Constructor
     *
     * @access    public
     * @param    array    initialization parameters
     */
    public function __construct($params = array())
    {
        if (count($params) > 0)
        {
            $this->init($params);
        }

        log_message('debug', "Pagination Class Initialized");
    }

    // --------------------------------------------------------------------

    /**
     * Initialize Preferences
     *
     * @access    public
     * @param    array    initialization parameters
     * @return    void
     */
    public function init($params = array())
    {
        if (count($params) > 0)
        {
            foreach ($params as $key => $val)
            {
                if (isset($this->$key))
                {
                    $this->$key = $val;
                }
            }
        }
    }

    // --------------------------------------------------------------------

    /**
     * Generate the pagination links
     *
     * @access    public
     * @return    string
     */
    public function get_links()
    {
        // If our item count or per-page total is zero there is no need to continue.
        if ($this->total_rows == 0 OR $this->per_page == 0)
        {
            return '';
        }

        // Calculate the total number of pages
        $num_pages = ceil($this->total_rows / $this->per_page);

        // Is there only one page? Hm... nothing more to do here then.
        if ($num_pages == 1)
        {
            return '';
        }

        // Determine the current page number.
        $OB = ob::instance();

        if ($OB->config->item('enable_query_strings') === TRUE OR $this->page_query_string === TRUE)
        {
            if ($OB->input->get($this->query_string_segment) != 0)
            {
                $this->cur_page = $OB->input->get($this->query_string_segment);

                // Prep the current page - no funny business!
                $this->cur_page = (int) $this->cur_page;
            }
        }
        else
        {
            if ($OB->uri->segment($this->uri_segment) != 0)
            {
                $this->cur_page = $OB->uri->segment($this->uri_segment);

                // Prep the current page - no funny business!
                $this->cur_page = (int) $this->cur_page;
            }
        }

        $this->num_links = (int)$this->num_links;

        if ($this->num_links < 1)
        {
            throw new PaginationException('Your number of links must be a positive number.');
        }

        if ( ! is_numeric($this->cur_page))
        {
            $this->cur_page = 0;
        }

        // Is the page number beyond the result range?
        // If so we show the last page
        if ($this->cur_page > $this->total_rows)
        {
            $this->cur_page = ($num_pages - 1) * $this->per_page;
        }

        $uri_page_number = $this->cur_page;
        $this->cur_page = floor(($this->cur_page/$this->per_page) + 1);

        // Calculate the start and end numbers. These determine
        // which number to start and end the digit links with
        $start = (($this->cur_page - $this->num_links) > 0) ? $this->cur_page - ($this->num_links - 1) : 1;
        $end   = (($this->cur_page + $this->num_links) < $num_pages) ? $this->cur_page + $this->num_links : $num_pages;

        // Is pagination being used over GET or POST?  If get, add a per_page query
        // string. If post, add a trailing slash to the base URL if needed
        if ($OB->config->item('enable_query_strings') === TRUE OR $this->page_query_string === TRUE)
        {
            $this->base_url = rtrim($this->base_url).'&amp;'.$this->query_string_segment.'=';
        }
        else
        {
            $this->base_url = rtrim($this->base_url, '/') .'/';
        }

          // And here we go...
        $output = '';

        // Render the "First" link
        if  ($this->cur_page > ($this->num_links + 1))
        {
            $output .= $this->first_tag_open.'<a href="'.$this->base_url.'">'.$this->first_link.'</a>'.$this->first_tag_close;
        }

        // Render the "previous" link
        if  ($this->cur_page != 1)
        {
            $i = $uri_page_number - $this->per_page;
            if ($i == 0) $i = '';
            $output .= $this->prev_tag_open.'<a href="'.$this->base_url.$i.'">'.$this->prev_link.'</a>'.$this->prev_tag_close;
        }

        // Write the digit links
        for ($loop = $start -1; $loop <= $end; $loop++)
        {
            $i = ($loop * $this->per_page) - $this->per_page;

            if ($i >= 0)
            {
                if ($this->cur_page == $loop)
                {
                    $output .= $this->cur_tag_open.$loop.$this->cur_tag_close; // Current page
                }
                else
                {
                    $n = ($i == 0) ? '' : $i;
                    $output .= $this->num_tag_open.'<a href="'.$this->base_url.$n.'">'.$loop.'</a>'.$this->num_tag_close;
                }
            }
        }

        // Render the "next" link
        if ($this->cur_page < $num_pages)
        {
            $output .= $this->next_tag_open.'<a href="'.$this->base_url.($this->cur_page * $this->per_page).'">'.$this->next_link.'</a>'.$this->next_tag_close;
        }

        // Render the "Last" link
        if (($this->cur_page + $this->num_links) < $num_pages)
        {
            $i = (($num_pages * $this->per_page) - $this->per_page);
            $output .= $this->last_tag_open.'<a href="'.$this->base_url.$i.'">'.$this->last_link.'</a>'.$this->last_tag_close;
        }

        // Kill double slashes.  Note: Sometimes we can end up with a double slash
        // in the penultimate link so we'll kill all double slashes.
        $output = preg_replace("#([^:])//+#", "\\1/", $output);

        // Add the wrapper HTML if exists
        $output = $this->full_tag_open.$output.$this->full_tag_close;

        return $output;
    }
}
// END Pagination Class

/* End of file Pagination.php */
/* Location: ./base/libraries/Pagination.php */